Intel ITANIUM ARCHITECTURE - SOFTWARE DEVELOPERS MANUAL VOLUME 1 REV 2.3 Manual page 427

Data Nested TLB vector (0x1400)
Name
Cause For memory references, the data TLB entry needed for a data reference is absent and
PSR.ic is 0. Note: Data Nested TLB faults cannot occur during IA-32 instruction set
execution, since PSR.ic must be 1.
Interruptions on this vector:
IR Data Nested TLB fault
Data Nested TLB fault
Parameters IIP, IPSR, IIPA, IFS, ISR are unchanged from their previous values; they contain
information relating to the original interruption.
ITIR – is unchanged from the previous value.
IFA – is unchanged from the previous value and contains the original address of the
data being referenced.
IIB0, IIB1 – If implemented, the IIB registers are unchanged from their previous
values. Please refer to
(IIB0-1 – CR26, 27)" on page 2:42
Notes This fault occurs when PSR.dt 1 and PSR.ic is 0 on a load, store, semaphore, and
faulting non-access instructions. It also occurs when PSR.dt is 0 and PSR.ic is 0 for a
regular_form probe instruction. Finally it can occur when PSR.rt is 1 and PSR.ic is 0 on
a RSE mandatory load/store operation. Since the operating system is in control of the
code executing at the time of the nested fault, it can by convention know which register
contains the address that raised the nested event. As the PSR.ic bit is 0 on a nested
fault, the IFA contains the original data address if the original interruption was caused
by a data TLB fault. If the translation table entry required by the nested miss handler
has not yet been allocated, then the address in the IFA will be passed to the operating
system page fault handler. If the translation for the entry is available then the general
register containing the nested fault address must be moved to the IFA prior to the
insert. The ISR contains the ISR for the original faulting instruction, and not the ISR for
the instruction that caused the nested fault.
Volume 2, Part 1: Interruption Vector Descriptions
Section 3.3.5.10, "Interruption Instruction Bundle Registers
for details on the IIB registers.
2:179